Robert Plant has found unreleased Led Zeppelin tapes. After digging up some of the band's long-neglected demos, Plant said he can't wait to put them out – as long as John Paul Jones will give the OK.

"I found some quarter-inch spools recently," Plant told BBC 6 Music, "and there's some very, very interesting bits and pieces that probably will turn up [soon]." The recordings are intended for a series of remastered and deluxe Led Zeppelin reissues, due some time in the next year. "Hidden gems – now that should be the name of [our] band, really," Plant said.

Plant has already gone over this material with Jimmy Page: "I had a meeting with Jimmy," he recalled. "We baked them up and listened to them." But it's not the band's guitarist who is the obstacle to their release. "I'm desperately trying to [use] this one track – or the two tracks – [with] John Paul Jones singing lead," he revealed. "And so far [Jones is] up to giving me two cars and a greenhouse [to leave] them [off] the album."

Jones might be right to be bribing his former bandmate. Led Zeppelin's 1977 tour is notorious, among fans, for the way Jones filled in for Sandy Denny on performances of the duet Battle Of Evermore. "Jonesy shouldn't sing," declared one forum poster. "As genius as he is with all of his other musical talents, he can't be good at everything." The multi-instrumentalist has also sometimes recorded vocals for his solo work.

Earlier this summer, Jones said that although Plant has floated ideas of reuniting Led Zeppelin next year, "[my] 2014 is full of opera". The 67-year-old is preparing an adaptation of August Strindberg's 1908 play The Ghost Sonata (Spöksonaten). "[Opera] is unlike anything else," he said.